This invention relates to a vitamin assay, and, more particularly, to an assay for determining the extent of conversion of a vitamin to one or more analogues thereof due to interaction between the vitamin and the other components of a multicomponent composition containing the vitamin.
Multivitamins are frequently ingested in the form of pills, and are frequently used to supplement human foods and a variety of animal chows. Vitamins are chemicals and are capable of reacting among themselves and with other substances to form vitamin analogues. Despite this knowledge, little, if any, attention has been paid to the possibility that vitamin analogues might be formed in multivitamin pills, supplemented foods, and animal chows. Essentially no attention has been paid to the possibility that vitamin analogues might be harmful in the sense that they might be absorbed from the gastrointestinal tract and might interfere with the activities of various enzymes that require vitamins for activity.
This lack of awareness and concern is readily apparent from the standard production procedures and quality control methods that are employed in the pharmaceutical industry, and the human and animal food industries. These procedures consist of adding known amounts of various vitamins to a given preparation, and then assaying the amounts of the individual vitamins present after the preparation has been manufactured and stored under normal conditions. "Losses" are frequently encountered, and this problem is remedied by simply increasing the amounts of individual vitamins that are added to the preparations. The reason for the "loss" is not explored, and no attention is given to the possibility that such "losses" might actually represent the conversion of vitamins into vitamin analogues, rather than the complete destruction or evaporation of the vitamins themselves. The problem of identifying vitamin analogues, at least by means of standard analytical techniques, is an extremely difficult one, because so many different vitamins are present in multivitamin and multivitamin-mineral formulations, supplemented foods and animal chows.
Recent studies conducted by the present inventor have shown that CN-cobalamin is converted to a number of cobalamin analogues by the concerted action of vitamin C, thiamine, and copper sulfate. These studies have also shown that such interactions are responsible for the presence of cobalamin analogues in a number of popular multivitamin-mineral pills and animal chows, and that additional cobalamin analogues are formed when these preparations are merely dissolved in water and incubated at body temperature for several hours. In addition, these studies have shown that such cobalamin analogues are absorbed from the gastrointestinal tract of laboratory animals, and that they either lack cobalamin activity or actually inhibit cobalamindependent enzymes, when they are injected parenterally into laboratory animals. These findings suggest that cobalamin analogues are being ingested by humans, and that they may be detrimental. It is furthermore suggested by these studies that other vitamins may be converted into analogues in various multivitamin preparations, and that these analogues may also be detrimental.